[simon]

My 500 f4 seems to have developed a focusing issue Quite regularly when i half press the shutter on both my 7D and 40D the focusing mechanism seems to freeze if it is well out of focus and i have to move the lens until i find a point were it is in or nearly in focus then it will start to autofocus. Initially the problem seemed to be with the 40D only and more prominent when i had the 1.4 attached, I tried it a couple of times on a MK111 and couldn't get the issue to happen so i sent the 40 away to have it checked and other repairs done and treated myself to a 7D but the prob is still apparent and seems to be getting worse
Has anyone else experienced this issue?

I have emailed Colchester Camera Repair but they can't repair 500mm lenses as "due to the focal length they cannot project" it and suggested contacting Canon direct

Has anyone sent lenses of his type to Canon? If so how long do they take for repair, how did you pack it? etc etc any help/advice appreciated

[JohnZ]

It could be the extremely cold weather affecting it ?

[simon]

Originally Posted by JohnZ

It could be the extremely cold weather affecting it ?

Thanks but its not, the initial probs started around September with the 40D and is just that as it is now getting worse and while the weather is not the best i thought i would try and get it sorted

[GYRob]

Originally Posted by simon

My 500 f4 seems to have developed a focusing issue Quite regularly when i half press the shutter on both my 7D and 40D the focusing mechanism seems to freeze if it is well out of focus and i have to move the lens until i find a point were it is in or nearly in focus then it will start to autofocus. Initially the problem seemed to be with the 40D only and more prominent when i had the 1.4 attached, I tried it a couple of times on a MK111 and couldn't get the issue to happen so i sent the 40 away to have it checked and other repairs done and treated myself to a 7D but the prob is still apparent and seems to be getting worse
Has anyone else experienced this issue?

I have emailed Colchester Camera Repair but they can't repair 500mm lenses as "due to the focal length they cannot project" it and suggested contacting Canon direct

Has anyone sent lenses of his type to Canon? If so how long do they take for repair, how did you pack it? etc etc any help/advice appreciated

is this when the limit switch is set to the full focus range as it can seem to get lost (not freez as such ) morso with a low contrast subject and with the TC on , try cleaning the lens and camera contacs too.
Rob.

[simon]

Originally Posted by GYRob

is this when the limit switch is set to the full focus range as it can seem to get lost (not freez as such ) morso with a low contrast subject and with the TC on , try cleaning the lens and camera contacs too.
Rob.

I'll give it a clean and also try switching to different limits, The reason i think it freezes is because it doesn't seem to drive the focus until it finds a point to start on, guess it could be what you call "lost', I'll try to get time this weekend to play with/without T/C and switch the limits

[tdodd]

Simon, I don't have a 500/4L but that behavious sounds a lot like somehow you've disabled focus search in the custom functions of your 40D and 7D. Not an easy thing to do by accident but I can't think of a better reason why the 1D3 is fine while two other bodies are not.

[Cashie]

I agree with Tim, because I had the same with mine on the 40D, played about with custom functions found it was set to search off, reset it & now it's fine.

[simon]

Originally Posted by tdodd

Simon, I don't have a 500/4L but that behavious sounds a lot like somehow you've disabled focus search in the custom functions of your 40D and 7D. Not an easy thing to do by accident but I can't think of a better reason why the 1D3 is fine while two other bodies are not.

Just checked the 7D and lo your right will check the 40 latter. Something in the back of my mind is ringing bells, i think i switched it off when i first got the 7d after reading a post on another forum or somewhere where an example of setting up the CF on a 7D was posted and i set up accordingly
Good job i posted here before sending the lens to canon

Cheers all

[GYRob]

Originally Posted by simon

Just checked the 7D and lo your right will check the 40 latter. Something in the back of my mind is ringing bells, i think i switched it off when i first got the 7d after reading a post on another forum or somewhere where an example of setting up the CF on a 7D was posted and i set up accordingly
Good job i posted here before sending the lens to canon

Cheers all

think you need to buy Tim a pint :)
Rob.

[simon]

Originally Posted by GYRob

think you need to buy Tim a pint :)
Rob.

There's one in the post